<script setup>
import { ref, onMounted } from 'vue';
import { ElMessage } from 'element-plus';
import { User, Lock } from '@element-plus/icons-vue';
import { useRouter } from 'vue-router';

const isRegister = ref(false);
const isForgotPassword = ref(false);
const form = ref();


//注册、登录、忘记密码的表单数据
const formModel = ref({
  username: '',
  password: '',
  rePassword: '',
  newPassword: '',
  confirmNewPassword: ''
});


//整个表单的校验规则
const rules = {
  username: [
    { required: true, message: '请输入用户名', trigger: 'blur' },
    { min: 5, max: 10, message: '用户名必须是5-10位的字符', trigger: 'blur' }
  ],
  password: [
    { required: true, message: '请输入密码', trigger: 'blur' },
    {
      pattern: /^\S{6,15}$/,
      message: '密码必须是6-15位的非空字符',
      trigger: 'blur'
    }
  ],
  repassword: [
    { required: true, message: '请再次输入密码', trigger: 'blur' },
    {
      pattern: /^\S{6,15}$/,
      message: '密码必须是6-15的非空字符',
      trigger: 'blur'
    },
    {
      validator: (rule, value, callback) => {
        if (value !== formModel.value.password) {
          callback(new Error('两次输入密码不一致!'))
        } else {
          callback()
        }
      },
      trigger: 'blur'
    }
  ],
  newPassword: [
    { required: true, message: '请输入新密码', trigger: 'blur' },
    {
      pattern: /^\S{6,15}$/,
      message: '密码必须是6-15位的非空字符',
      trigger: 'blur'
    }
  ],
  confirmNewPassword: [
    { required: true, message: '请再次输入新密码', trigger: 'blur' },
    {
      pattern: /^\S{6,15}$/,
      message: '密码必须是6-15的非空字符',
      trigger: 'blur'
    },
    {
      validator: (rule, value, callback) => {
        if (value !== formModel.value.newPassword) {
          callback(new Error('两次输入密码不一致!'))
        } else {
          callback()
        }
      },
      trigger: 'blur'
    }
  ]
};

const initLocalUsers = () => {
  if (!localStorage.getItem('users')) {
    localStorage.setItem('users', JSON.stringify([
      { username: 'admin', password: '123456' }
    ]))
  }
};

onMounted(initLocalUsers);

// 登录模块
const login = async () => {
    await form.value.validate();
    const users = JSON.parse(localStorage.getItem('users'));
    const foundUser = users.find(user => 
      user.username === formModel.value.username && 
      user.password === formModel.value.password
    );
    if (foundUser) {
      localStorage.setItem('isLoggedIn', 'true');
      localStorage.setItem('currentUser', JSON.stringify(foundUser));
      ElMessage.success('登录成功');
      router.push('/main/cart');
    } else {
      ElMessage.error('用户名或密码错误');
    }
};

// 注册模块
const register = async () => {

    await form.value.validate();
    const newUser = {
      username: formModel.value.username,
      password: formModel.value.password
    };
    const users = JSON.parse(localStorage.getItem('users'));
    if (users.some(user => user.username === newUser.username)) {
      return ElMessage.error('用户名已存在');
    }
    users.push(newUser);
    localStorage.setItem('users', JSON.stringify(users));
    ElMessage.success('注册成功');
    isRegister.value = false;
};

// 忘记密码模块，重置密码
const resetPassword = async () => {
    await form.value.validate();
    const users = JSON.parse(localStorage.getItem('users'));//JSON.parse()方法将JSON字符串转换为对象。
    const foundUser = users.find(user => user.username === formModel.value.username);
    if (foundUser) {
      foundUser.password = formModel.value.newPassword;
      localStorage.setItem('users', JSON.stringify(users));//JSON.stringify()方法将JavaScript对象转换为JSON字符串。
      ElMessage.success('密码重置成功');
      isForgotPassword.value = false;
    } else {
      ElMessage.error('用户名不存在');
    }

};

const router = useRouter();
</script>

<template>
  <el-row class="login-page">
    <el-col :span="24" :offset="0" class="form">
      <!-- :model : 单向数据绑定，将表单数据传递给表单组件进行校验 -->
      <el-form :model="formModel" :rules="rules" ref="form" size="large" autocomplete="off" v-if="isRegister">
        <el-form-item>
          <h1>注册</h1>
        </el-form-item>
        <el-form-item prop="username">
          <el-input v-model="formModel.username" :prefix-icon="User" placeholder="请输入用户名"></el-input>
        </el-form-item>
        <el-form-item prop="password">
          <el-input v-model="formModel.password" :prefix-icon="Lock" type="password" placeholder="请输入密码"></el-input>
        </el-form-item>
        <el-form-item prop="repassword">
          <el-input v-model="formModel.repassword" :prefix-icon="Lock" type="password" placeholder="请再次输入密码"></el-input>
        </el-form-item>
        <el-form-item>
          <el-button class="button" @click="register" type="primary" auto-insert-space>
            注册
          </el-button>
        </el-form-item>
        <el-form-item class="flex">
          <el-link type="info" :underline="false" @click="isRegister = false">
            ← 返回
          </el-link>
        </el-form-item>
      </el-form>
      <el-form :model="formModel" :rules="rules" ref="form" size="large" autocomplete="off" v-else-if="!isForgotPassword">
        <el-form-item>
          <h1>登录</h1>
        </el-form-item>
        <el-form-item prop="username">
          <el-input v-model="formModel.username" :prefix-icon="User" placeholder="请输入用户名"></el-input>
        </el-form-item>
        <el-form-item prop="password">
          <el-input v-model="formModel.password" name="password" :prefix-icon="Lock" type="password"
            placeholder="请输入密码"></el-input>
        </el-form-item>
        <el-form-item class="flex">
          <div class="flex">
            <el-checkbox>记住我</el-checkbox>
            <el-link type="primary" :underline="false" @click="isForgotPassword = true">忘记密码？</el-link>
          </div>
        </el-form-item>
        <el-form-item>
          <el-button @click="login" class="button" type="primary" auto-insert-space>登录</el-button>
        </el-form-item>
        <el-form-item class="flex">
          <el-link type="info" :underline="false" @click="isRegister = true">
            注册 →
          </el-link>
        </el-form-item>
      </el-form>
      <el-form v-bind:model="formModel" :rules="rules" ref="form" size="large" autocomplete="off" v-else>
        <el-form-item>
          <h1>忘记密码</h1>
        </el-form-item>
        <el-form-item prop="username">
          <el-input v-model="formModel.username" :prefix-icon="User" placeholder="请输入用户名"></el-input>
        </el-form-item>
        <el-form-item prop="newPassword">
          <el-input v-model="formModel.newPassword" :prefix-icon="Lock" type="password" placeholder="请输入新密码"></el-input>
        </el-form-item>
        <el-form-item prop="confirmNewPassword">
          <el-input v-model="formModel.confirmNewPassword" :prefix-icon="Lock" type="password" placeholder="请再次输入新密码"></el-input>
        </el-form-item>
        <el-form-item>
          <el-button class="button" @click="resetPassword" type="primary" auto-insert-space>
            重置密码
          </el-button>
        </el-form-item>
        <el-form-item class="flex">
          <el-link type="info" :underline="false" @click="isForgotPassword = false">
            ← 返回
          </el-link>
        </el-form-item>
      </el-form>
    </el-col>
  </el-row>
</template>

<style scoped>
.login-page {
  height: 100vh;
  background-color: #fff;
}
.form {
  display: flex;
  flex-direction: column;
  justify-content: center;
  user-select: none;
  margin-top: 200px;
  width: 300px;
  height: 300px;
}
.title {
  margin: 0 auto;
}
.button {
  width: 100%;
}
.flex {
  width: 100%;
  display: flex;
  justify-content: space-between;
}
</style>